moekis



@nimh tatrs jgstwt @ffice IMPROVEMENT IN ROTARY PUMPS AND ENGINES.

@La Stimuli rentra tuin tigrst tettcrs @anni mit making @mi nt tigt smut.

TO ALL WHOM IT MAY OONCERN:

Be it know that we, DEXTER D. HARDY and J oHN J. MORRIS, both of Cincinnati, Hamilton county, State of Ohio, have invented certain new and useful Improvements in Rotary Engines and Pumps; and we do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, making part of this specification.

Our invention consists in the employment in a double cylinder, having inner `tongues or projections, (as

patented in combination by us, March 5, 1861,) of rotary pistons, formed by arcs of circles of different diameters, connected by cpicycloid or other suitable curves, the cpicycloid faces being supplied with elastic gibs.

Our invention further consists in the employment of set screws, to prevent the lateral play andwvear of the pistons.

In the accompanying drawings- Figure 1 is a cross section of a rotary engine or pump, embodying our invention.

Figure 2 is a sectionalplan of the same. p y

A is the case or cylinder, having the inner projections D D', as fully described and patented by ns in com-` bination, with a peculiar shaped piston, bearing date March 5, 1861. B B are the rotary pistons, formed, as shown, by arcs of circles, a a and b', of diiferent diameters, connected by epicycloid or other suitable curves c. The pistons B B are turned to it accurately the diameter of' the cylinder and length between the heads C C', and are adapted to make a joint between each other on line X, by the close contact of the large and small arcs a b. In opera-tion as anengine the line X remains tight, by reason of the pistons necessarily revolving at that point in theopposite direction to the inward current of i steam, and steam cannot escape past the arcs a a", in` consequence of its partial condensation causing it to water pack in passing through such an `extended surface;` In operation as a pump no leakage of consequence can occur, and as the surfaces barely touch, there is no perceptible friction or wear. As it is practically impossible to make the epicycloid `faces c make a joint ivithout i danger of' striking hard in rotation, we provide these faces with elastic gibs G, slotted at g, to allow` the water or steam pressure to balance. The gibs G have springs H fitted behind them, to give the necessary elasticity. i

We have found by experience that when the shafts I I are not conined'laterally in their journals, the steam or water pressure will force the pistons B B hard up against one or other of the heads C C,'tliereby` causing an immense amount of friction and considerable Wear. To prevent this lateralplay we provide the. frame of the machine, or shaft bearings, with set-screws J, against which the ends of both shaftsiare made to revolve and keep in place. In the accompanying drawing the set-screws vJ are shown but 'to one end ofthe machine, and a modification of. the sameis shown at the opposite end, consisting of turned Vs in the shafts at d, and corresponding babbited boxes e, the babbit metal'1 tting the 'Vfs ofthe' shafts and preventing lateral play. p

We do not desire to confine ourselves to the use of tivo arcs, a a or b b', to each piston B B. A greaterA or less number of arcs and epicycloids may be used at will, but preference has been given by us to the form as shown. The gear Wheels K connect the shafts I'I together, and preserve the pistons B B in the same relative position.

A We claim as new herein, and of our invention 1. Constructing the rotary pistons, B B, of' arcs of circles a a' b b', of different diameters, connected` by epicycloid faces c, in the described combination with the elastic gibs G, as and for the purpose specified.

2. We claim, as arranged with the above combination, the set-screws J, for preventing lateral play of the shafts and pistons, as set forth.

In testimony of which invention we hereunto set,o`ur. hand.`

DEXTER D. HARDY, JOHN J. MORRIS.

Witnesses:

Cms. H. FIsK, W. D. DAL'roN. 

